Digital Commons Network^™

An Investigation On Bubble Departure In Subcooled Flow Boiling, Brian J. Stumm

Theses

A summary of the major theoretical models available for departure diameter prediction in sub-cooled flow boiling is presented. A new model is developed to predict the forces acting on a bubble at the instance of departure by introducing a control volume approach for the front and the rear halves of the bubble. The predictions from the model are compared with experimental data obtained in the Thermal Analysis Laboratory in the Mechanical Engineering Department at Rochester Institute of Technology. Two competing mechanisms are identified as being responsible for bubble departure. To obtain clear evidence of the dominate mechanism, high speed photography …

Design Of A Hardware Efficient Key Generation Algorithm With A Vhdl Implementation, James A. Goeke

Theses

The design and implementation of a key-generation algorithm will be discussed. The steps in the procedure consist of choosing a baseline algorithm for comparison, designing a new algorithm, testing and comparing the algorithms using C language programs, and then implementing the new algorithm using VHDL. The final result of testing the algorithm implemented in VHDL will be compared to the original results obtained from the C program implementing the new algorithm. C language programs of the chosen algorithms will be developed to verify their similarity and functionality. The results will be used to decide if the new algorithm selected for …

A Metaphysical And Linguistic Approach To Type Design And Typography, Ivan Terestschenko Rocha

Theses

Significant changes have taken place in the type design as a result of what has often been termed "the desktop revolution." With the popularization and increased availability to the average person of typographic tools formerly available only to professionals type is slowly moving into the realm of personal communication. This move has sparked significant controversy among the various schools of typographic thought, but little consensus exists. As well, technological developments are contributing to a widening of the definition of what constitutes a typeface. This study, then, will examine the current views of type design as an art form and the …

Optical Signal Processing And Real World Applications, Patrick Naulleau

Theses

It is common to want to correct signals that have been corrupted by wideband dispersion. If the dispersion is caused by a system whose transfer function has a flat amplitude function and a nonlinear phase function, such as is the case with a ltig periodic antenna, the signal can be corrected via a matched filter. In this paper various optical implementations of the matched filter, including one and two dimensional systems, are investigated. The 2D Fourier Filter, along with several simplifications, demonstrating its power, are simulated. The optical implementations of these systems are also discussed. The problem of phase detection …

An Uncertainty Analysis Of A Color Tolerance Database, Mitchell Balonon-Rosen

Theses

A database designed to develop, evaluate and compare color-difference formulae, particularly for use within the suprathreshold industrial-sized range, so named for its importance in many commercial transactions, has been under development at the Munsell Color Science Laboratory. The database consists of two independent data sets, previously published. The sets and the experimental conditions under which they were derived were analyzed to determine the appropriateness of pooling the data. The earlier of the two studies had associated statistics which indicated a population of highly precise observers. The latter study's population displayed a significantly greater level of uncertainty. The current work concluded …

Conversion Of Solid Ink Density And Dot Gain Specifications Into Colorimetric Specifications, Theera Tangvichachan

Theses

With the advent of the spectrophotometer as an alternative to the densitometer for pressroom applications, it becomes desirable to use a single three-color overprint halftone gray patch for controlling color on the press. As a consequence, the need for new specifications in colorimetric units, rather than SID and dot gain units, arises. The purpose of this study was to conduct a mathematical conversion of the traditional SID and dot gain specifications into the colorimetric specifications, in terms of the CIELAB coordinates. The FIPP dot gain and SID specifications were applied to the gray patch contained in the Gretag CMS3 color …

The Effects Of Fluctuations In Solid Ink Density On Color Variation For Conventional And Grey Component Replacement Separations When Printing Process Color On Newsprint, Eric Matthew Pawlow

Theses

A color separation technique known as Gray Component Replacement, or GCR has been an option available to high-end drum scanner operators for the past eight years. Recently, GCR has been made available by lower-end color system vendors as well. GCR consists of removing the least predominant process color ink in a unit area, reducing the remaining colored inks by the same amount and replacing the "gray component" of the color with black ink. One of the reported benefits of the GCR technique is that more consistency can be realized during a pressrun. If this is in fact true, the first …

No Way Out, Janice Leigh Johnson

Theses

None provided.

Monolithic Silicon Opto-Electro-Mechanical Light Modulator, Ching-Horng Wu

Theses

A Fabry-Perot light beam modulator of the reflection-type has been designed with process and performance parameters optimized. This design takes advantage of the economies of surface micromaching using silicon substrates and selected thin films. High performance with a low drive voltage are achieved using electrostatic actuation of a thin polysilicon diaphragm. The diaphragm is a novel corrugated structure which has maximum compliance and maintains planarity during actuation. In addition, the corrugationsuspension used provides an improved linearity of amplitude modulation response as a function of the actuation voltage.

A preliminary version of this device has been fabricated through a contract foundry …

Cross-Disciplinary Use Of Metaphor, Jeff Arbegast

Theses

The initial thesis proposal was grand in scope. I wanted to create a methodology, a process that could assist R.I.T students in approaching problems with a metaphorical mindset. The metaphorical mind would be a mind that could approach a creative problem making rich associations and connections.

Graphic Design Career Information, Danielle Grace Plouffe

Theses

None provided.

Influence Of Ink Sequence On Color's Hue And Saturation In Four Color Halftone Screen Printing, Aristotelis Platon Bougàs

Theses

The screen printing process has been the least understood and studied versus other imaging methods in the graphic arts industry. As equipment configurations improve and a continuous technological development and need for high quality output persists, this fascinating process becomes increasingly popular in several end-use applications. Such as in packaging, labeling, durable graphic films printing and even short run large format halftone graphics. There is a serious need for further deep scientific analysis of the process and its variables. One of the poorly investigated sides of the four color screen printing is the effect that ink placement has to the …

Trigeminal Neuralgia, Through The Eyes Of The Medical Illustrator, Brian D. Mcdermott

Theses

None provided.

Business Forms Industry's Response To Edi And Electronic Substitutes, Michael J. Hill

Theses

This project has two primary objectives. Both objectives will be achieved through research of current data and the creation, distribution and analysis of a business forms industry survey. The first objective was to draw attention to the growing demand for electronic substitutes for traditional printed business forms, and educate the business forms industry about the biggest threat and opportunity of these technologies, Electronic Data Interchange (EDI). This was accomplished by outlining the technology and processes of EDI and describing the various benefits of EDI over traditional printed business forms systems. Such educational descriptions and analysis were necessary due to the …

Simulation Of A Morphological Image Processor Using Vhdl - Part Ii: Control Mechanism, Hao Chen

Theses

Very high speed integrated circuit Hardware Description Language (VHDL) is utilized in this project to model a Morphological Image Processor (MIP) Array. Both behavioral and structural models have been established at the system level, and the simulation results from both models are consistent with each other. The successful implementation of the models accomplishes our original goal to document the MIP with VHDL. It is observed from the project that VHDL is a powerful language. It is flexible since it can be used to model any level of a system independent of the technology.

Simulation Of A Morphological Image Processor Using Vhdl - Part I: Mathematical Components, Wei-Chun Chen

Theses

Very high speed integrated circuit Hardware Description Language (VHDL) is utilized in this project to model a Morphological Image Processor (MIP) Array. Both behavioral and structural models have been established at the system level, and the simulation results from both models are consistent with each other. The successful implementation of the models accomplishes our original goal to document the MIP with VHDL. It is observed from the project that VHDL is a powerful language. It is flexible since it can be used to model any level of a system independent of the technology.

Reduction Of Acoustic Feedback Oscillations By Use Of Spectrum Shifting, Youssef Abdelilah

Theses

The problem of whistling noise or self-oscillation in public address systems operating in closed halls or rooms can be very disturbing to the listeners. This noise is sustained when the positive acoustic feedback, of the public address-room system, meets the oscillation criteria. This feedback system results from the acoustic sound signal reflected off the room walls and any other obstacles in the room, originating from the public address speakers and then re-entering the microphone.

When all of the audio signal components entering the public address system are shifted by a frequency increment Δf of 6 Hz, an increase of 5 …

Measures For Estimating The Need For Flexibility In A Manufacturing Facility, Raghu Chilukuri

Theses

Manufacturing technology is in the midst of on-going developments stemming from rapid improvements in machine tools, computers and robots. These developments present engineers with greater challenges and opportunities in designing more complex and productive systems. The concept of flexibility was defined by authors like Jaikumar, Son & Park, and Buzacott. The various challenges can be partly over come by building flexibility into the various systems. Various operational or raw measures are described as they help managers to understand the kind and extent of flexibility embedded in their production process and allow them to make informal judgement on new equipment.

Various …

An Improved Human Gait Model Incorporating The Effects Of Muscle Activity And Joint Friction, Tae Ho Choi

Theses

In designing an artificial leg for an amputee, it is important to find those underlying principles which determine the normal human gait. For this purpose we have developed a model of human walking, in which it is possible to predict an optimal gait at any given speed of walking based on the principle of minimum mechanical energy consumption.

Our model is an extension of the model proposed by Mochon and McMahon (1980). Their model assumes that during the swing phase of walking mechanical energy is conserved. Non-conservative forces due to muscle activity are assumed to occur during the double support …

Entrance Effects For Short Catalytic Combustion Monoliths, Dong Dai

Theses

Catalytic combustion/incineration is becoming increasingly important in modern industrial processes. This thesis work investigates the importance of heat and mass transfer entrance effects in short catalytic combustion monoliths, and includes these effects in an engineering model. Consideration is limited to laminar-flow heat and mass transfer in a circular tube, in which Prandtl number is close to unity, as is the case for air. Thermal, mass and velocity boundary layer growths are considered with inlet conditions assumed uniform at a monolith bed entrance. Conservation equations are solved assuming laminar, steady-state flow, with constant wall temperature, and negligible axial diffusion of heat …

Partial Vlsi Implementation Of The Architecture For Reusable Components (Arc), Deepak Kakadasam

Theses

This work describes a novel VLSI implementation of the Architecture for Reusable Components (ARC) processor, using Hardware Description Language (HDL). The main goal here is to achieve efficient execution of reusable software through proper hardware support. This involves the hard wired implementation of each instruction designed for the ARC processor.

Instructions are broken down into their logical functions, then modeled and simulated through the hierarchical design methods that HDL offers. The structural model of the processor has been developed and simulated. The purpose here has been to begin work on the design and implementation of the ARC processor.

The instructions …

Application Of Imaging Pyrometry For Remote Temperature Measurements, Michael B. Kaplinsky

Theses

The radiometric model of an IR image sensor has been developed. Based on this model, the application of imaging pyrometry to remote temperature measurements has been investigated. This analysis provides the estimation of temperature accuracy achievable by imaging pyrometry in conjunction with a number of radiometric methods. The detection of radiation emitted across the full spectral bandwidth of the imager as well as utilization of narrow-passband filters was analyzed for a target with known emissivity.

The methods of two-wavelength ratio radiometry and multi-wavelength radiometry were considered for the targets with unknown emissivity. The optimal selection of the wavelengths for the …

Modal Control Of Flexible Beam Using Smart Mateirals, Sujata Mallepalle

Theses

In this work, the dynamics and control aspects of a vibrating flexible beam using modal analysis are studied. To damp the vibrations of the system, the vibrations of each mode has to he controlled, which can he done if we know the individual mode shape. and the resonance frequency. These quantities can be derived mathematically or measured experimentally with a spectrum analyzer. Individual modal velocities can be computed by integration of the product of beam velocity and the mode shape, over the interval of beam length. The integration is carried out using numerical methods. The necessary discrete ordinates are obtained …

Optical Flow Determination And Motion Analysis, Qian Wang

Theses

Optical flow, also known as image flow, is of fundamental importance in the processing of image sequences. Various approaches to determine optical flow have been proposed --- others continue to appear. Using several sets of real image sequences, here, the results of three different approaches to the the determination of optical flow are reported, the approaches are the Gradient-based approach, the Correlation-based approach and the Correlation-feedback approach. The comparisons are primarily empirical, and they show that the performance of these different algorithms differs significantly among the different image sequences, indicating that there does not exists one superior algorithm which could …

A Programmable Integrated Power Supply For The Electrostatic-Drive Micromotor, Chao Ye

Theses

A 6-phase bipolarized, high-voltage power supply with rectangular pulse shape has been designed to study the special operational characteristics of various electrostatic-drive micromotors. In particular the design powers the variable-capacitance side-drive micromotor. This power supply provides variable frequency, variable voltage, and variable duty-cycle control. Simulation has been used extensively in the design and design verification.

The bipolarization (dual voltage polarity) of each pair of the phases reduces physical clamping of the rotor to the electrical shield beneath it. Thus, bipolarization of the voltage supplied to the stator nodes reduces charge build-up on the rotor.

The output frequency range varying from …

Fingerprint Pattern Recognition For Medical Uses, Feng You

Theses

The purpose of my research is to provide a method to automatically classify fingerprints into three subgroups: whorl, loop and arch, which can help medical scientists to study the relationship between fingerprint patterns and medical disorders. In the research, two different kinds of approaches were developed. The first one is performing pattern recognition in the frequency domain, which uses the feature of Fourier spectrum. That is, prominent peaks in the spectrum give the principal direction of fingerprint patterns. Using the above feature, we can obtain the principal direction of every subregion, after which the pattern of the whole image can …

A Study Of Pulsation Of Chest Wall Using Microwave Interferometer, Paul Zeno

Theses

The microwave interferometer is utilized to pick up vibrations of the anterior chest wall produced by the cardiac activity. The objective of this project is to find the causes of different peaks in the output of the microwave interferometer. The output of the microwave interferometer is recorded simultaneously with EKG and jugular pressure pulses. Eighteen subjects had their mechanical vibrations of the chest wall, EKG and jugular pressure pulses recorded. The processed interferometer data, when compared with EKG and jugular pressure pulses appear to have a close relation to the mechanical events in the cardiac cycle. Four peaks in the …

Computer Aided Finite Element Stress Analysis Of A Three Dimension Mandibular Bone Model Using I-Deas Software, Yixiong Xu

Theses

A three dimensional model of half of the mandibular bone, with 487 tetrahedra elements and 1,047 nodes, is established and analyzed by means of I-DEAS software. The masseter muscle is assumed to be 15° deviation from y-axis, and the Umetani boundary conditions are allowed to be varied. A 337 lb force was applied along the midline of the mandible to simulate a trauma force caused by the auto accident. The maximum principal stress is 18,400 psi and the minimum principal stress is -1,340 psi. Depending on the experimental results of dispalcement and maximum principal stress, the conclusions are drawn: 1) …

Forward Kinematics Solution Of A Special Class Of General Stewart Platforms, Jian Li

Theses

A Stewart platform is a fully parallel, six-degree-of-freedom manipulator mechanism. A platform manipulator has a fixed platform acting as base, a mobile platform on which end-effector is mounted, and in-parallel kinematics chains (legs) between the two platforms. Although some direct position kinematics solutions for Stewart platforms of simplified geometry have been represented, to the best of our knowledge, no close-form direct kinematics solution for the general Stewart platform is available yet.

A common feature of six-degree-of-freedom Stewart platform of simplified geometry is the use of pairs of concentric ball joints. Due to inevitable manufacturing and assembly errors, practically there are …

Development Of A Model For An Objective Minimum Resolvable Temperature Difference Characterization Of An Infrared Camera, Christine Issa Mourad

Theses

The parameter almost universally adopted by the infrared community for describing the overall performance of a thermal imaging camera is the minimum resolvable temperature difference. Unfortunately, this criterion is subjectively determined by a group of observers and as a consequence significantly varying results can be obtained at different times. This project describes work on an approach which ultimately aims to replace the observers by a computer-aided installation that simulates the human process by which the MRTD is estimated. The simulation is based on a direct measurement of signal to noise ratio in the image of the target and a determination …